Distillation of Iron, Nickel, and Other Allied Metals.

Progress, Volume I, Issue 10, 1 August 1906, Page 277

Distillation of Iron, Nickel, and Other Allied Metals.

In a recent number of the Comptes rendus de I' Academic dcs Science, Moissan describes further experiments on the distillation of metals in the electric furnace. This investigator, who has already succeeded in distilling copper, gold, and the metals of the platinum group, has now turned his attention to iron and its allies (vide The Time-> Engineering Supplement, February 7, 1906, page 47 ; and March 7, 1906, page 75). Manganese was found to be the most volatile metal of this series, a specimen containing 2 per cent, of carbon readily distilled when heated with a current of 500 amperes and an E.M.F. of no volts. The distilled metal was distinctly crystalline. Another sample of this element free from carbon but con taming 4 per cent, of silicon was volatilised even more readily, but the ebullition was rendered irregular by the violent evolution of occluded gases. Nickel and chromium came next m order of volatility, about half a pound of the former distilled completely in nine minutes with 500 amperes and no volts. In the case of iron, an

*Since the above was written Tate has put on the market an important machine with much simpler parts and at a greatly reduced price. I have been using one of these for some time and am thoroughly satisfied with it in every way. — J.W.K.

experimental difficulty arose owing to the molten iron carbide occluding gases and these subsequently with considerable violence as the boiling point was reached, so that a large proportion of the metal was projected from the crucible. In this case the best result was obtained by heating the metal gradually with a current of 1,000 amperes and 1 10 volts, when 50 per cent, of a 2lb. specimen was volatilised in 20 minutes. The boiling point of uranium is somewhat higher than that of iron, a current of 900 amperes and no volts being required to volatilise this element. Molybdenum and tungsten were found to be the least volatile metals of the series and only boiled regularly after prolonged heating with the foiegomg current. Like iron and manganese, molybdenum occludes gases when in the molten condition. Tungsten has the highest boilins; point of any metal hitherto examined in the electric furnace.